Part Three: The Transfer Ports

[wcorey]

Jms seems to favor heavy transfer mods along with higher crankcase compression. I've seen several times where he ground through to the outside of transfer tunnels and had to use jb weld to seal them back up.

At least some of the reason for that is nothing really special.

When you cut the band and base and raise the exhaust, the transfers typically need to be raised quite a bit and in attempting to just maintain the original roof angles, you simply run out of material and break through the top. Enhancement of the original angles can get really sketchy, particularly on the primary side outside corners.
That the transfers open closer to 90 degrees than the exhaust exacerbates this even further, though it could be counteracted somewhat with more case comp by means of means of more blowdown and/or higher intake...

 

[mettee]

I think that would be application specific.

Some tricks work in some saws, and other tricks in others. Since they all like different things, might work and it might not. Finding that special trick is the hard part.

 

[Stump Shot]

I know it's a sore subject for a lot of people, but I think it's worth mentioning for the sake of transfer porting theory. Jms seems to favor heavy transfer mods along with higher crankcase compression. I've seen several times where he ground through to the outside of transfer tunnels and had to use jb weld to seal them back up. And his saws seem to run. I know some will disagree with that statement. So, does anyone think its worthwhile to hog out transfers thus increasing crankcase volume but then making back up for it by increasing crankcase compression?

Sent from my SM-G930V using Tapatalk

First off you would have to explain how increasing crankcase volume increases crankcase pressure, the two do not go together.
Especially on models where the lowers are too large to begin with, as that much volume can't fit through the uppers.
It will allow the sweep angle to be lessened for better redirecting of flow, if only this was taken advantage of. This also however comes at at a huge loss in torque/power. Run well and cut well are also two very different things free wheeling rpm isn't everything.
Wallering out the intake only increases the problem and lessens the pull from the carburetor adding another.
At least now I understand why the grinding particles were added to the crankcase, it was to add compression and here all this time I thought it was just negligence. Brilliant!
There's been enough cylinders sent to supply beer can manufacturing and this is the only positive step to society made by all this nonsense.
All this befoonery serves, is a snake oil salesmen type marketing gimmick to sell folks that don't know any better into his line of maxed out BS.
I only have a low opinion of his work after seeing it, lots of other folks with first hand experience that lost a lot of money, have an even lower one.

 

[Ketchup]

Asymmetric transfer uppers and lowers:


The crank weights are also asymmetric. Every single upper opens at a different time and has a unique angle and volume. It appears one side supplies the majority of the flow. The other side has a steeper angle, especially the secondary, and is ramped. This saw has a large squish band (0.0380”) and a finger ported exhaust (stock compression is unimpressive).

This cylinder and others have a perpendicular exhaust outlet, so creating a swirl may help exhaust flow.

It seems like the engineers really went crazy, but this saw is at the top of power delivery for it’s size. I wish I knew how much the design was to accomodate a top handle and how much made power.

 

[MustangMike]

Stump, interesting post, but I hope you don't mind if I play Devils Advocate!

First, I have nothing but distain for JMS, his shoddy procedures and how he cheated folks, but I also remember some of the 064/660 saws he sent to the CT GTG and I will tell you they were VG runners, so he knew something. Perhaps they were just his "I got lucky" saws that he saved to send to us, I don't know, but they ran.

Secondly, I have had this intake debate with other builders, and my thoughts are that is it similar to why the lowers are larger than the uppers, which don't even fully open.

1) The intake goes into the crankcase, not directly into the combustion chamber, so IMO volume is more important than velocity. If the upward piston movement generates 5 psi of vacuum, the more area that exists when it first opens the more air/fuel mix will be sucked in.

2) For the upper transfers, direction and velocity are important, and if the lowers have more area for the pressure, this will increase the velocity of the uppers. It is like a garden hose, the larger the diameter of the hose, and the smaller the spray jet, the more velocity you will have.

Those are my thoughts on these issues, for whatever they are/or are not worth! Opposing comments are always welcome!

 

[srcarr52]

Big transfer work well when they are paired with decently long blowdown and minimal intake duration to keep the crankcase compression as high as possible.

Still, hogged out lowers don't do anything if the uppers can't match or direct the incoming charge.

As for JMS's 064/066's, they are just a copy of someone else's work.

 

[Mastermind]

I enjoy just reading along rather than attempting to interject anything. I think maybe I learn more that way.

 

[srcarr52]

I enjoy just reading along rather than attempting to interject anything. I think maybe I learn more that way.

Curmudgeon!

 

[Mastermind]

Curmudgeon!

Meh......

I just woke up one day and realized that all we were really doing was playing the same game over and over. In my time on these forums I've seen people show up and steer the discussions back to things we tried and gave up on years and years ago. These days I'd rather just keep my thoughts to myself instead of getting in the way of anyone's learning processes.

 

[Stump Shot]

Stump, interesting post, but I hope you don't mind if I play Devils Advocate!

First, I have nothing but distain for JMS, his shoddy procedures and how he cheated folks, but I also remember some of the 064/660 saws he sent to the CT GTG and I will tell you they were VG runners, so he knew something. Perhaps they were just his "I got lucky" saws that he saved to send to us, I don't know, but they ran.

Secondly, I have had this intake debate with other builders, and my thoughts are that is it similar to why the lowers are larger than the uppers, which don't even fully open.

1) The intake goes into the crankcase, not directly into the combustion chamber, so IMO volume is more important than velocity. If the upward piston movement generates 5 psi of vacuum, the more area that exists when it first opens the more air/fuel mix will be sucked in.

2) For the upper transfers, direction and velocity are important, and if the lowers have more area for the pressure, this will increase the velocity of the uppers. It is like a garden hose, the larger the diameter of the hose, and the smaller the spray jet, the more velocity you will have.

Those are my thoughts on these issues, for whatever they are/or are not worth! Opposing comments are always welcome!

Send him one of your saws then. Lol

 

[Time's Standing Stihl]

Big transfer work well when they are paired with decently long blowdown and minimal intake duration to keep the crankcase compression as high as possible.

Still, hogged out lowers don't do anything if the uppers can't match or direct the incoming charge.

As for JMS's 064/066's, they are just a copy of someone else's work.

Don’t forget 394/395...

 

[MustangMike]

Send him one of your saws then. Lol

Not likely!!!

 

[MustangMike]

Everything has limitations, and I do not increase the size of the lower transfers, but, they are already much larger than the upper transfers (which do not fully open) and I believe there is a valid reason for that.

 

[Stump Shot]

Everything has limitations, and I do not increase the size of the lower transfers, but, they are already much larger than the upper transfers (which do not fully open) and I believe there is a valid reason for that.

Some are made really big and some are made really small. It's just the few that are already too large that it doesn't make sense to make bigger. At least that's the way I see it.

 

[Mastermind]

Some are made really big and some are made really small.

You just described all the girls I dated.....they were all fun though.

 

[mettee]

I enjoy just reading along rather than attempting to interject anything. I think maybe I learn more that way.

Us guys young in the game would love you to interject and add your knowledge. Im only working on my own stuff so no way I can learn from doing 10-15 saws.

Help us learn if you don't mind.

 

[Mastermind]

Us guys young in the game would love you to interject and add your knowledge. Im only working on my own stuff so no way I can learn from doing 10-15 saws.

Help us learn if you don't mind.

I'll always share my notes on any model.....and I've posted an ass load of threads on various models.

The single most thing that made me shut down sharing my work was Jason Stratton telling me that if someone sent him a saw he'd never done, all he had to do was find one of my threads on that model. So......the way I see it, I helped that sucker of big black cocks rip people off. Because of that, I seriously doubt I'll ever publish another build thread, or publicly share anything that will help anyone do what I've spent years learning.

I'll be here helping to keep this forum free of trash like JMS though.......believe that.

 

[Stump Shot]

You just described all the girls I dated.....they were all fun though.

You know the routine...
Pics or it never happened. Lol

 

[srcarr52]

I'll always share my notes on any model.....and I've posted an ass load of threads on various models.

The single most thing that made me shut down sharing my work was Jason Stratton telling me that if someone sent him a saw he'd never done, all he had to do was find one of my threads on that model. So......the way I see it, I helped that sucker of big black cocks rip people off. Because of that, I seriously doubt I'll ever publish another build thread, or publicly share anything that will help anyone do what I've spent years learning.

I'll be here helping to keep this forum free of trash like JMS though.......believe that.

I feel similar, it saddens me knowing that I information I shared ultimately increased his ability to rip people off.

Never the less, Randy, I appreciate all you have shared with and done for this community of knuckle heads.

 

[Lightning Performance]

Us guys young in the game would love you to interject and add your knowledge. Im only working on my own stuff so no way I can learn from doing 10-15 saws.

Help us learn if you don't mind.

Well....oh my...

Mikes number two theory is about pressure not velocity. Sorry Mike.

Ya'll said it right. JMS was a poor copy cat. Moving on

You'll learn a lot after the first five and try this out

Or this

Your Welcome
Remember now you, you love your chainsaw, your chainsaw loves you and makes fire.
Do you know about precious?
You have a better chance of figuring out women.
This won't help but it is cool

Most folks won't even try that.

Oh, btw. That is what we build. It all goes back to hot rods from the forties and board-track bikes before them.

Love the Precious, right Dave?